diff options
| author | Hannes Reinecke <hare@suse.de> | 2016-02-19 09:17:11 +0100 |
|---|---|---|
| committer | Martin K. Petersen <martin.petersen@oracle.com> | 2016-02-24 03:27:02 +0100 |
| commit | 00642a1bff0c2bc72d78d13598e26eb44caa1e85 (patch) | |
| tree | b7f20704ddde02d07f7880bfcc18201612a7f0dc | |
| parent | scsi_dh_alua: Use workqueue for RTPG (diff) | |
| download | linux-00642a1bff0c2bc72d78d13598e26eb44caa1e85.tar.xz linux-00642a1bff0c2bc72d78d13598e26eb44caa1e85.zip | |
scsi_dh_alua: Allow workqueue to run synchronously
Some arrays may only capable of handling one STPG at a time,
so this patch adds a singlethreaded workqueue for STPGs to be
submitted synchronously.
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| -rw-r--r-- | drivers/scsi/device_handler/scsi_dh_alua.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 8318852fc437..a3cb06955adc 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -64,6 +64,7 @@ /* device handler flags */ #define ALUA_OPTIMIZE_STPG 0x01 #define ALUA_RTPG_EXT_HDR_UNSUPP 0x02 +#define ALUA_SYNC_STPG 0x04 /* State machine flags */ #define ALUA_PG_RUN_RTPG 0x10 #define ALUA_PG_RUN_STPG 0x20 @@ -76,6 +77,7 @@ MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than static LIST_HEAD(port_group_list); static DEFINE_SPINLOCK(port_group_lock); static struct workqueue_struct *kaluad_wq; +static struct workqueue_struct *kaluad_sync_wq; struct alua_port_group { struct kref kref; @@ -686,6 +688,7 @@ static void alua_rtpg_work(struct work_struct *work) int err = SCSI_DH_OK; struct alua_queue_data *qdata, *tmp; unsigned long flags; + struct workqueue_struct *alua_wq = kaluad_wq; spin_lock_irqsave(&pg->lock, flags); sdev = pg->rtpg_sdev; @@ -695,6 +698,8 @@ static void alua_rtpg_work(struct work_struct *work) spin_unlock_irqrestore(&pg->lock, flags); return; } + if (pg->flags & ALUA_SYNC_STPG) + alua_wq = kaluad_sync_wq; pg->flags |= ALUA_PG_RUNNING; if (pg->flags & ALUA_PG_RUN_RTPG) { pg->flags &= ~ALUA_PG_RUN_RTPG; @@ -705,7 +710,7 @@ static void alua_rtpg_work(struct work_struct *work) pg->flags &= ~ALUA_PG_RUNNING; pg->flags |= ALUA_PG_RUN_RTPG; spin_unlock_irqrestore(&pg->lock, flags); - queue_delayed_work(kaluad_wq, &pg->rtpg_work, + queue_delayed_work(alua_wq, &pg->rtpg_work, pg->interval * HZ); return; } @@ -722,7 +727,7 @@ static void alua_rtpg_work(struct work_struct *work) pg->interval = 0; pg->flags &= ~ALUA_PG_RUNNING; spin_unlock_irqrestore(&pg->lock, flags); - queue_delayed_work(kaluad_wq, &pg->rtpg_work, + queue_delayed_work(alua_wq, &pg->rtpg_work, pg->interval * HZ); return; } @@ -751,6 +756,7 @@ static void alua_rtpg_queue(struct alua_port_group *pg, { int start_queue = 0; unsigned long flags; + struct workqueue_struct *alua_wq = kaluad_wq; if (!pg) return; @@ -768,10 +774,12 @@ static void alua_rtpg_queue(struct alua_port_group *pg, scsi_device_get(sdev); start_queue = 1; } + if (pg->flags & ALUA_SYNC_STPG) + alua_wq = kaluad_sync_wq; spin_unlock_irqrestore(&pg->lock, flags); if (start_queue && - !queue_delayed_work(kaluad_wq, &pg->rtpg_work, + !queue_delayed_work(alua_wq, &pg->rtpg_work, msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) { scsi_device_put(sdev); kref_put(&pg->kref, release_port_group); @@ -990,10 +998,16 @@ static int __init alua_init(void) /* Temporary failure, bypass */ return SCSI_DH_DEV_TEMP_BUSY; } + kaluad_sync_wq = create_workqueue("kaluad_sync"); + if (!kaluad_sync_wq) { + destroy_workqueue(kaluad_wq); + return SCSI_DH_DEV_TEMP_BUSY; + } r = scsi_register_device_handler(&alua_dh); if (r != 0) { printk(KERN_ERR "%s: Failed to register scsi device handler", ALUA_DH_NAME); + destroy_workqueue(kaluad_sync_wq); destroy_workqueue(kaluad_wq); } return r; @@ -1002,6 +1016,7 @@ static int __init alua_init(void) static void __exit alua_exit(void) { scsi_unregister_device_handler(&alua_dh); + destroy_workqueue(kaluad_sync_wq); destroy_workqueue(kaluad_wq); } |